At about an hour past midnight on an October night in 1932, Arthur
Millier, art critic for the Los Angeles Times, wandered through
Olvera Street in downtown Los Angeles. There he found Mexican artist
David Alfaro Siqueiros, sitting on a scaffold, "sweating in an undershirt"
and "painting for dear life."

Siqueiros was struggling to finish his largest work since he had
arrived in the city earlier in the year. It was a 24-by-5.48-meter
(80-by-18-foot) mural, situated on the outside second-story wall
of Olvera Street's Italian Hall.

Color rendering prepared by conservator Agustín Espinosa in 1990, showing how the mural might have looked when
first unveiled.

The mural had been commissioned by gallery owner F. K. Ferencz
of the Plaza Art Center, who instructed that its theme be "tropical
America." Siqueirosa participant in the Mexican Revolution and
a seasoned Communist Party organizer who had just spent a year in
Mexican prison for his activitieshad no intention, he later said,
of painting "a continent of happy men, surrounded by palms and parrots,
where the fruit voluntarily detached itself to fall into the mouths
of the happy mortals."

However, for most of the weeks that Siqueiros and his team of assistants
labored on the mural, the work's central image remained unpainted
and the artist's ultimate intent unclear. Then, as Millier reports,
the day before the scheduled unveiling, Siqueiros sent everyone
home and worked through the night to complete the mural's main figure.
Set in front of a Maya-like pyramid, he was an Indian crucified
on a double cross with an American eagle above him. In the upper
right-hand corner of the mural, two revolutionary soldiers were
depicted, one pointing his rifle at the eagle.

The work was unveiled October 9, 1932. When the scaffolding came
down, "onlookers gasped," reported Millier in the Times. "No one
but the author had been able to visualize the close-knit powerful
design so long shaded and concealed by those scaffolds."

For a number of the city's artists, including those who had assisted
Siqueiros with the mural, the work was tremendously exciting. "It
had guts in it," recalled one over 40 years later. "It made everything
else at the time look like candy box illustrations. Many of the
artists said, 'My God! This is wonderful vocabulary.'"

Such enthusiasm was not universal. While acknowledging the mural
as "an interesting experiment," one review asked "Why get hysterical
about Mexican art?...Why imitate it and adopt it in our own country,
whose traditions are entirely alien to it all?" The reviewer pleaded
to "keep the Mexican motif in the Mexican quarter."

The negative reaction did not end with criticism of the mural's
aesthetic aspects. Its political content prompted outrage from some
of the city's civic leaders, including those who had established
Olvera Street as a Mexican marketplace two years earlier. Not long
after the mural's completion, Ferencz was forced to cover over the
most visible third with white paint. Within a year, the entire mural
was painted over.

The controversy did little for Siqueiros' political standing in
the United States. A renewal of his six-month visa was refused,
and he was forced to leave the country. But the episode by no means
brought a halt to Siqueiros' career. His stature as an artist continued
to grow, and today he is known as one of the triumvirate of Mexican
muralists, along with Diego Rivera and José Clemente Orozco, who
reawakened the world to the dynamic possibilities of mural art.

As for América Tropicalas the mural is now knownit
was forgotten for decades, left to languish in the strong Southern California
sun. In the early 1970s, the first efforts to preserve the now-fading masterpiece
began, but it wasn't until the late 1980s that, with the assistance of the Getty
Conservation Institute, substantial steps were taken to save the only surviving
public mural by Siqueiros in the United States.

The Neglected Masterpiece

The techniques and materials employed in the creation of América Tropical
Siqueiros first tried out several weeks earlier in a fresco class he taught
at Chouinard Art School. Over a two-week period, he and his students painted
upon one of the school's walls an outdoor mural called Street Meeting.
(This mural, too, was an object of controversy and ultimately covered over.)
In preparation for the mural, a pneumatic drill was used to roughen the wall
surface and give greater adhesion to the white cement on which the mural was
painted. Because the cement dried rapidly, Siqueiros used an airbrush extensively
in applying paint.

A similar approach was utilized in the making of América Tropical.
"From here," Siqueiros later said of his experimentation on the mural, "all
my methods changed on the road to a modern technology for social modern art."

The artist no doubt hoped that the experimental methodology would
prove durable. Indeed, one contemporary review of the mural concluded
that "rains will never wash it off, nor sun dim its details, for
it is cement!"

Time did not confirm this appraisal. In the decades that followed
its creation and covering over, the mural displayed the effects
of sun, rain, smog, and earthquakes. The painting layer beneath
the white paint began to deteriorate as the white paint itself slowly
eroded. In places the mural faded and peeled. Portions of the plaster
started detaching from the wall. Due to the high level of pollution
in the area, the mural's surface became coated in dirt.

Siqueiros in 1971. Photo: Luis Garza.

In the early 1970s, art historian Dr. Shifra Goldman and Los Angeles
filmmaker Jesús Salvador Treviño spearheaded the first
attempts to preserve the mural. Stimulated by their efforts, Siqueiros
himself made plans to paint a replica of the central portion of
the mural on a series of wooden panels, which he intended to present
to the city of Los Angeles. Unfortunately, the artist died in January
1974, before the panels were completed.

In 1977 Jean Bruce Poole joined the staff of El Pueblo Park, the
city agency that today administers the historic block of buildings
on Olvera Street. As the park's senior curator, Ms. Poole was surprised
to learn of the mural's existence. "I said, 'Look, you've got a
masterpiece here. It's an absolute outrage; you've got to do something
to save it.'" Joining forces with others already working for the
mural's preservation, she sought technical assistance and resources
to save what remained. But despite a growing interest in the mural
by the city's Mexican-American community, financial support for
its conservation did not materialize. Because of the lack of funds,
no preservation measures were taken other than erecting a protective
plywood shed around the mural.

The 1990 cleaning and consolidation of the paint layer
during the first phase of the conservation program. Photo by Nancy
Kaye.

In 1987 Ms. Poole met with then-Getty Conservation Institute Director Luis
Monreal and Special Projects Directornow Institute DirectorMiguel
Angel Corzo, to discuss América Tropical. Mr. Corzo, a native of
Mexico City who grew up seeing the murals of Siqueiros, Rivera, and Orozco,
had viewed América Tropical for the first time just a few months
earlier. "I was really appalled that nothing had been done to conserve it,"
he recalled. "There seemed to be no sense of respect for the work of art, which
was very saddening." Because of the mural's aesthetic and symbolic value, he
felt strongly that the Institute should get involved.

Later that year, David Scott and Michael Schilling of the Institute's
Scientific Program took paint samples from the site and prepared
an analysis of the paint pigments used in the mural. Subsequent
analysis of a sample removed from the site in 1971 indicated that
the paint's binder was probably cellulose nitrate. The exposure
to direct sunlight and pollution of a binder consisting of cellulose
nitrate, over a period of many years, would significantly contribute
to the deterioration of the mural's painting layer.

In 1988 the Institute officially joined with El Pueblo Park and
the Friends of the Arts of Mexico Foundation to undertake the mural's
rescue. After consultation with conservators and engineers, a comprehensive
program for saving América Tropical was developed.

The Conservation Effort

The first phase of the mural's conservation began in 1990. Mexican
conservators Agustín and Cecilia Espinosa headed the conservation
team, assisted by two students from the wall paintings conservation
training program of the Courtauld Institute of Art in London. Over
the course of several months, the team removed the remaining white
paint from the mural, cleaned and consolidated the painting layer,
and reattached loosened cement plaster to the brick wall. Traces
of asphalt running along the base of the painting were also eliminated.

Photo taken in 1932 showing whitewash covering the most visible third of the mural. Photo courtesy of El Pueblo de los Angeles
Historic Park.

In May 1991 the Institute installed an environmental monitoring
station adjacent to the mural. For over a year and a half, the station
measured such factors as wind speed and direction, rainfall, temperature,
humidity, and the movement of sunlight across the mural's surface.
The data collected provided valuable information about environmental
conditions at the mural to assist in the designing of a protective
shelter by Altoon & Porter, a leading Los Angeles architectural
firm with experience working on historic structures.

In the spring of 1994, the Institute took another step in its comprehensive
assessment of the mural's condition. With equipment designed by
Eric Lange, a Fellow at the Institute, the entire mural was documented
using digital imaging.

From the beginning of the preservation program, public access to the mural
has been a primary objective. An estimated 1.5 million people come to Olvera
Street annually. Many would undoubtedly make the mural part of their visit if
access were provided. At the same time, because of its artistic and historic
importanceand its significance to the city's large Mexican-American populationAmérica Tropical has the potential to draw new visitors of its own.

Several major steps remain before public access can be achieved.
The first is the seismic stabilization of the Italian Hall and adjacent
buildings. This work is scheduled to be started this year.

In addition, plans are being developed for a permanent mural shelter,
a public viewing platform, and a historical information area that
can provide visitors with a context for viewing the mural. The Institute,
together with other organizations, will reach out to the public
and private sectors to underwrite the cost of constructing the mural
shelter and the public areas. Once a shelter is installed, the mural's
final cleaning, stabilization, and consolidation can proceed.

This last effort will not, unfortunately, return América Tropical to its original glory. The problematic nature of the materials
used in its creation, combined with years of deplorable civic neglect,
have left the Siqueiros masterpiece a shadow of its original incarnation.
Much of its color is gone.

Nevertheless, the artistic power of the work remains. "You've only
got to look at that mural to see the strength in the painting,"
says Jean Bruce Poole. "Even faded, it is still immensely strong."

Ms. Poole, now director of El Pueblo's Historic Museum, believes
that even in its present condition, the mural is "telling a story,"
one of political controversy and artistic expression. "The mural
is tremendously important because it's part of the city's history,"
she explains. "Even the fact that it's been so badly treated is
part of the history."

Luis Garza, the Institute's consultant coordinator for the mural project, agrees.
"América Tropical has come to epitomize the historical mistreatment
of art," he says. Seeing the mural as it is today vividly demonstrates what
is lost by such mistreatment. Its destruction by civic leaders provides a contemporary
lesson in the consequences of intolerance.

However, as he also points out, the mural is much more than a symbol
of artistic censorship and prejudice. América Tropical profoundly
influenced the mural movement so interwoven into today's Los Angeles,
a city with over fifteen hundred public murals. Its legacy in public
art, despite its treatment, is considerable.

The conservation of the mural and its return to public view, Mr.
Garza believes, can help heal divisions within the community. "The
political and social issues the mural so dramatically depicts engage
all of us," he observes. "The process of conserving América Tropical gives those in our community that rare opportunity to get
to know one another better."

This, as much as anything, forms the basis for the Getty Conservation
Institute's involvement in the project. As Harold Williams, President
of the Getty Trust, has declared, the Trust's long-term goals in
its home community include "creating an urban environment in which
diversity is a source of strength rather than of conflict."

After over sixty years of existence, América Tropical today transcends
the controversy that accompanied its birth. "It's a universal work of art,"
says Miguel Angel Corzo. "It represents a social struggle which we all can understand
now. It's a mural for the whole city."

Mural Update

For 16 straight days in April, América Tropical was once
more the site of intense activity. Again scaffolding went up, but
the effort on this occasion was not mural creating but recording.
Using the Siqueiros mural as a first field site, a small team of
Getty Conservation Institute staff, led by Eric Lange, a British
conservator and GCI Research Fellow, tested a new system for direct
digital capture of a wall painting in situ.

In contrast to conventional photography, digital image capture
utilizes a specially designed computerized camera back to record
images directly onto a computer hard drive or optical disk. Thus,
although the image can be viewed, manipulated, and output as if
it were a photographic image, the information is actually recorded
and stored as a block of binary code (i.e., a series of 1's and
0's), rather than as a "picture" on film.

Digital imaging of wall paintings in the field offers a number
of advantages over traditional methods. While on site, conservators
can record cracking patterns, plaster joins, previous restorations,
biological deterioration, and other important features using a program
such as Adobe Photoshop to produce color-coded transparent "overlays"
directly on the images. These layers can be viewed individually
or in combination, and can be turned on or off at the touch of a
button. Another advantage of digital capture is that it allows the
conservator to instantly magnify or enhance particular areas or
features of interest.

"What we set out to do was to see if digital capture could be done
on-site by conservators in a way that was feasible and practicable,"
says Mr. Lange, who researched and designed the digital documentation
system and organized this test at América Tropical. The commercially
available components of the system included a Hasselblad camera
with a Zeiss lens and Leaf digital camera back, and a Quadra 950
computer with extended ram and a 20-inch color monitor. Custom components
included special scaffolding that moved on a self-leveling trackway,
and a camera dolley that rode on its own track at the top of the
scaffolding. This system allowed for the camera to be positioned
with considerable accuracy.

One hundred fifty-six images were captured in a grid 6 images high
by 26 images wide. Once the on-site recording phase was completed,
lower resolution copies of the original (12.6 Mb) files were "mosaiced"
together to create a single image of the mural. Since the painting
is covered by a very narrow shelter, it is impossible to view the
site in its entirety, and until now no single image of the mural
in its current state existed. Without the capability for digital
calibration and adjustment of illumination, color balance, and registration
as each shot was captured, it would have been extremely difficult
to achieve sufficient consistency with film photography to produce
a seamless composite of 156 images.

The precision of digital photography has another important advantage:
Since the information is actually recorded in a numeric rather than
photochemical way, it establishes a baseline to which future recordings
can be compared to provide accurate and quantifiable analyses of
change. Similar comparisons could be made using images in the ultraviolet,
infrared, and thermographic spectra.

Traditional methods of site documentation often produce large quantities
of information in a variety of formats: binders of slides and photographic
prints, oversized files of drawings and transparent overlays, field
logbooks, etc. "In terms of information management," says Mr. Lange,
"digital documentation can provide immediate, on-site integration
of all images, diagrams, condition reports, treatment notes, and
other materials generated in the fieldall of which can be stored
on a few magneto-optical disks. Furthermore, this information
is more accurate, more accessible, and easier to reproduce than
that generated by traditional techniques."